Prime minister elect Tony Abbott said during his campaign that Australia should stay out of any military involvement in Syria. Why? Because we are a middle power that carries heft in particular regions but have only limited ability to influence many global events, and because the Syrian civil war is a case of "baddies versus baddies".

The comment was immediately dubbed a gaffe by some commentators. Several Labor leaders pointed to it as proof that "simpleton" Abbott lacks the nous to represent Australia on the world stage, arguing he doesn't have the knowledge, experience, gravitas needed to represent Australia on the world stage. In fact, Abbott showed great maturity in counselling caution on such a complex issue, rather than rushing into a hasty endorsement of threatened military strikes.

David Cameron noted in his failed attempt to rally parliamentary support for British participation in the strikes, "the well of public opinion has been well and truly poisoned by the Iraq episode". Indeed. The debate showed three sets of concerns animating Britain’s MPs that are all highly pertinent to how Australia will respond: facts yet to be established, unclear legal basis of strikes, and insufficient thought to the goal and aftermath of the strikes. All three point to a posture of prudence for Australia.

On facts, over 100,000 people have been killed in the civil war. In most accounts, there is an elision which implies that this number is the total number of victims of regime brutality. The "baddies versus baddies" description better captures the truth: the total includes civilians, rebel fighters and government soldiers. This is not to deny the scale of the horror, but to nuance it. Graphic videos of chemical weapons victims compete with equally graphic videos of rebels executing soldiers – footage so shocking it made New York Times staffers physically ill.

On chemical weapons use specifically, we can be certain they have been used. But by whom? Strategic logic and circumstantial evidence are contradictory. The Assad regime has flouted the global norm to be among a tiny handful of countries not to sign the convention banning chemical weapons and destroying existing stockpiles. But elements on both sides are callous enough to use chemical weapons on innocent civilians. The rebels have been losing the war and are desperate to entangle the US on their side.

President Obama, perhaps unwisely, has drawn a red line around the use of these weapons. The regime, as the side winning the war, had no reason to use the weapons and every reason not to – a point that President Vladimir Putin has emphasised repeatedly. The evidence presented to date, while not definitive (there are unconfirmed reports of a Sunni Arab state supplying chemical weapons to the rebels), does point the finger of criminality at the regime. But did the rebels use chemical weapons on a smaller scale in March? In July, Turkish police reportedly caught al Nusra jihadists with 2kg of sarin.

On law, the only two legal grounds for military attacks are in defence against armed attack, or when authorised by the UN. Loose talk of invoking the responsibility to protect – the original version of which was authored by Gareth Evans and me back in 2001 – ignores the requirement that it must be routed through the Security Council, be in conformity with the UN Charter, and be protective, not retributive. A one-off limited unilateral strike by the US and France would violate all three conditions.

Which then raises the final question: what exactly is the point of a "narrow" and "limited" strike, how would it impact the stability of this strategically vital region, and how is it connected to a wider diplomatic strategy for resolving the Syria conflict? If it is one off, Assad can confidently go on the offensive afterwards with a free hand to do whatever he feels necessary. There is no clarity about how, where and by what means his allies – China, Russia, Iran, Shia militias – would retaliate. Russia’s attitude is described by one Middle East experts as: “in a race across a minefield, it is wise to let other runners overtake you.”

If the strikes do lead to Assad’s ouster, power would likely quickly fall into the hands of an even more murderous anti-western regime allied to al-Qaida. The ouster of Saddam Hussein in effect delivered Iraq to Iran. Does Washington really want to deliver Syria to al-Qaida next?

Abbott has been the more measured and calm leader-in-waiting who has learnt from the Iraq experience a decade ago, instead of a headstrong and impetuous warrior on the charge. He could play a more constructive role through Australia’s presidency of the Security Council by neither criticising Washington nor joining a new coalition for yet another war of choice in the Middle East.